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2,6-TOLUENE-DIISOCYANATE (TDI)
| CAS # | 91-08-7 | 
|---|---|
| Formula | C₉H₆N₂O₂ | 
| Synonyms | 2,6-toluene diisocyanate; 2,6-TDI; 2,6-diisocyanato-1-methylbenzene; 2,6-diisocyanatotoluene | 
| Physical description | Colorless to pale-yellow solid or liquid with a pungent odor. | ||
|---|---|---|---|
| Boiling point | 264-271°F | Molecular weight | 174.2 | 
| Freezing point/melting point | 68-72°F | Vapor pressure | 0.5 mmHg at 77°F for 80% 2,4:20%; 2,6 TDI mixture | 
| Flash point | Vapor density | 6 | |
| Specific gravity | 1.2244 at 68°F | Ionization potential | |
| Lower explosive limit (LEL) | 0.9% | Upper explosive limit (UEL) | 9.5% | 
| NFPA health rating | NFPA fire rating | ||
| NFPA reactivity rating | NFPA special instruction | ||
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | T177 | 
|---|---|
| Sampling group | |
| Sampler/Sampling media | Isocyanate Sampling Filter Kit - GFF (37 mm, open-faced) coated with 1 mg 1-(2-pyridyl)piperazine [SLTC103] | 
| Sampling time* | 15 min | 
| Sampling volume (TWA)* | 15 L | 
| Sampling flow rate (TWA)* | 1 L/min | 
| Sampling volume (STEL/Peak/C)* | 
 | 
| Sampling flow rate (STEL/Peak/C)* | 
 | 
| Analytical method instruments | UHPLC | 
| Method reference | OSHA 5002 (fully validated) | 
| Notes | Refrigerate coated filters until used. Sample open-faced!! | 
| Special requirements | 
 | 
* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.
| Wipe Sampler/Sampling media | 
 | 
|---|---|
| Bulk Method | 
 | 
| Device | Detector tube | Hazard Assessment Test Kit for Aromatic Isocyanates | 
|---|---|---|
| Model/Type | Dräger - Toluene diisocyanate 0.02/a, 6724501 | 769-1002 | 
| Sampling information (see manufacturer instructions) | 25 strokes, approx 0.02-0.2 ppm range, uncertainty 30% | Isocyanate Surface and Dermal Sampling, Hazard Assessment Test Kit for Aromatic Isocyanates | 
| 
                                  OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak | 
                                  NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling | 
                                  ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling | |||||
|---|---|---|---|---|---|---|---|
| PEL-TWA | 
 | REL-TWA | 
 | TLV-TWA | 0.001 ppm (inhalable fraction and vapor) [2015] | PEL-TWA | 
 | 
| PEL-STEL | 
 | REL-STEL | 
 | TLV-STEL | 0.005 ppm (inhalable fraction and vapor) [2015] | PEL-STEL | 
 | 
| PEL-C | 
 | REL-C | 
 | TLV-C | 
 | PEL-C | 
 | 
| Skin notation | NA | Skin notation | NA | Skin notation | Y | Skin notation | NA | 
| Notes: | Notes: Not established | Notes: dermal sensitizer (DSEN), respiratory sensitizer (RSEN) | Notes: Not established | ||||
| Health factors: See NIH-NLM PubChem. | IDLH | ||||||
| Carcinogenic classifications: IARC-2B, NIOSH-Ca, NTP-R | Notes: 
 | ||||||
| AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: 0.01 ppm/0.15 ppm/0.6 ppm | |||||||
Additional Resources and Literature References
| NOAA: CAMEO Chemicals - Toluene-2,6-diisocyanate NIOSH: Pocket Guide to Chemical Hazards - Toluene-2,6-diisocyanate Literature References 
 | 
Last Updated Date : 04/02/2025
